Input validation error in Asterisk Open Source and Certified Asterisk - CVE-2021-32558
Published: July 26, 2021
Vulnerability identifier: #VU55294
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2021-32558
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to insufficient validation of user-supplied input within the IAX2 channel driver chan_iax2.c. A remote attacker can send a packet that contains an unsupported media format and perform a denial of service (DoS) attack.
Affected software
Asterisk Open Source
Certified Asterisk
asterisk (Debian package)
Certified Asterisk
asterisk (Debian package)
How to mitigate CVE-2021-32558
Install updates from vendor's website.
Asterisk Open Source - addressed in versions 13.38.3, 16.19.1, 17.9.4, 18.5.1
Certified Asterisk - update to 16.8-cert10
asterisk (Debian package) - update to 1:16.16.1~dfsg-1+deb11u1
Certified Asterisk - update to 16.8-cert10
asterisk (Debian package) - update to 1:16.16.1~dfsg-1+deb11u1